This project starts from the desire to explore the limits of digital reproduction entrusted to a PC exclusively developed in terms of music playback, searching for the highest possible soumd quality (SQ).
For this aim I’ve based my system on the cics’ cMP2 project (developed by author and Audioasylum community since 2007) with a number of important changes dictated by the HW evolution over the past 18 months joined to my personal experiences during this time .
My audioPC has adopted the principles of cMP2: the BIOS settings, the changes to the OS (XP Pro SP2)and the software developed by cics himself: cplay (the player) and CMP shell, which is available free of charge from CMP ² | Main / HomePage here:cMP² | Main / HomePage

in this site you can also find all the information necessary for the construction, including the very intriguing theoretical assumptions.
it could be better to print the entire manual (nearly seventy pages) so you’ll can read it in your own good time
The differences from the cics’original project, however, lie in the HW choice , in the development of linear power supply and in the aim of the project himself, since the original cMP2 borns as a digital server needing an external DAC, while mine wants to be an all-in-one unit, making use of expected synergy between the cMP2 project and the presence in the market of a high quality hifi sound card like the Asus Xonar Essence.
Results , in terms of sound quality , went far beyond my initial expectations and I forsee that it can be further refined in the future, but you pay for, alas, with a number of limitations which someone may find unacceptable, namely: - a) Management of Wave and FLAC files only, although with any sampling rate, through the file . cue- b) difficulty of managing playlists, complex enough to set only via a file .cue - c) Graphics-very basic, almost minimalist, I would say. - d)No ability to view album art or cover- e)Exclusive operation with ASIO
Project is optimized for Intel and Gigabyte mobo. This does not exclude AMD or other brands but keep in mind that there might be difficulties in the BIOS settings and the general functionality of the system using other components. This will be a dedicated audio-only device. The settings, in fact, do not allow any other use in practice.
Those who opt for such a choice has the monastic mood of the fans of the British amp (who remembers NVA, minimalist extreme, full of idiosyncrasies, but divine sounding), so this project is aimed at those who have voted exclusive pursuit of sound quality, the pleasure of hearing well reproduced music, not people searching for "colored beads and mirrors" or lower quality requirements.

The Hardware:
The original manual includes a section of cics suggestion of HW that can be followed precisely and successfully, since the result will be good anyway. But between the drafting of the manual and its updates, appeared on the market even better components that combine the basic design, whose basic philosophy can be reduced to "less is better", so I made a series of upgrades of the components that were better, until the current set of components that uses the most functional in my opinion this project between what you could find on the market.

In short it is a PC with HTPC full case, with internal SSD ( OS only) and external HDD for data.
Here are the components I’ve used: CPU: Intel i3 2100T choice for his exceptional efficiency. It consumes, in fact, only 32W and I can confirm that it is absolutely true. It has no competitors for now, awaiting the new processors Ivy Bridge should consume less and that will be compatible with the socket 1155. We'll see. COOLER: Thermaltake Slim X3 ventirad small and efficient. Once you set the system the fan is raised, so as to have a fanless system Mobo: Gigabyte GA-H67MA UD2H-B3 in my opinion the best buy at this time, also because of the fact that future processors Ivy Bridge will be compatible with the socket 1155 so you can upgrade later. The Z 68 has no advantage depending on the use to which the equipment is dedicated, IMHO.SSD: OCZ SSD 60 GB MLC Agility 2E 2.5''SATA II is also excessive for the sole OS. Obviously can be partitioned to test others SO. Case: Zalman HD 501 Black original design provides for an expensive HTPC case (there are beautiful and expensive) with a 7' touch screen . But I wonder: what is a touchscreen that resides in a facility, if we go to three meters away from the point of listening? Do yourself and give yourself the question to this answer.
I countered with a good VGA cable 5 m and an old flat screen (15 ') next to the listener, the less beautiful but much more economical and functional. You’ll must complete the picture with a keyboard and a wireless mouse RAM: Kingston 1GB 1333MHz DDR3 Non-ECC CL9: inexpensive, has never given trouble. As well not exist. But does exist, and it works well. No more than 1G, only to bench, otherwise the current consumption go up and jitter as well. PSU 1: X-400 Fanless Gold Plus 80 - 400 W Modular switching power supply ,probably the best ATX available today.
The goal is to replace it as soon as possible with a linear power supply , but to start I would say that it is almost obligatory choice PSU 2: PicoPSU 160 XT to associate with the previous one, which will feed through one of the 12V lines. This has to supply only the mobo, no other service or system should lie on it. PSU 3: Linear Power see here:Another Goldberg's variation on linear PSU theme ( with Belleson regulators) - audiodan@tiscali.it - Computer Audio Asylum
I must stress the ameliorative impact that linear PSU as described above has on the SQ. Soundboard: Asus Xonar Essence STX. Unfortunately, the PCI was abandoned by Intel as it 's deemeded obsolete, so in a few months I can easily predict that it will disappears at all. Mobo itself does not support it, and therefore the STX (PCI-E) becomes the obvious choice.

For those who want to enjoy to the limit (very high) to reach with this card I add these two links (in italian, I’m sorry)Asus Xonar ESSENCE ST/STX Parte prima: | Forum -X- NextHardwareAsus Xonar ESSENCE ST/STX Parte Seconda: l'upgrade estremo | Forum -X- NextHardware
where you'll find more news, I hope useful.
I do not need a CD-ROM drive because its use is limited to the installation of the operating system. If we can recover one just for this. Ripping of CD to be made into another PC, this one is reserved for listening music only.
External HDD: I use always WD Caviar Green , now 2TB. They are slow and also USB3 isn’t the cure of ​​all evils: it is earned a 20-30% faster, not more.
This non-performance is due to the slowness of the HD itself. Moreover they consumes very little and so far, (I own four of these), they have not betrayed. Pay attention on data back-up: losing thousands of albums for the failure of a HDD is a snap! Conclusions
This is my sound system:
Graham Michell Orbe-Arm 2.2, Lyra Titan i, step-up Uesugi, phono cable Synergistic Research Tricon
Lector CDP-7 (now sadly canned)
Pre-Conrad Johnson Evolution 20 SE with JPS power cord (6GK5 Mullard)
GRAAF GM 20 OTL-Final (ECC 6C33C + 88 + EF 184 Amperex Mullard)
ProAc Response 2.5 Speakers-
Straightwire Crescendo-signal and power cables
Manic development of power lines, separate digital and analog section, with the use of cables Nanotec Golden Strada, JPS, DH Labs, plugs and Oyaide, Furutech. Manic, indeed!

The most surprising thing is that I finally figured out, after thirty years of “audiophile militancy”, what it means to “the priority of the source”.
Many of defects attributed to my system, and for which I have spent over the years crazy amounts finding only palliatives, sometimes worse than the disease, has miraculously disappeared, and every day I amazing myself listening for music . It is not perfection but it's close enough, IMHO.
Whole works has cost a good effort, 18 months of study, testing, and various curses but I’ve been largely repaided by results so now I like to share with you . What remains now is to try and see if I just told a mere nothing.

boris81

12th August 2011 06:09 PM

Thank you for posting your findings, audiodany!
I am certainly interested in your experience concerning the linear power supply. The general notion seems to be that they are irrelevant because of the switching circuits available on the motherboard itself.

I have used a PC as a source for a while and never really had any sound issues. There's a lot of talk about interferences caused by switching circuits but I can't say I've experienced it. I don't see why acceptable sound shouldn't be possible from a computer.

I would like to report that I use the picoPSU-150-XT/12.5A 150W AC-DC power supply without problems. When I loop an output into an input on my Creative Audigy2 I can see the noise of the resulting signal rise to -80dB. I deem that acceptable. I can only hear negligible hiss at very high volume but I don't know if I can attribute that to my computer or somewhere further in the signal chain.

I use a PCIe to PCI adapter. They aren't cheap or easy to find but work well. Your build is obviously newer and cheaper but I will post a link to my machine for reference.

audiodany

12th August 2011 07:52 PM

Hi Boris81
it's true that a PC has a lot of switching regulators but it's true too that "garbage in/garbage out, amplified!!" if you feed your mobo with dirty current born from a switching PSU. PC could become a fantastic music machine, that's true.
If you want you'll can easy try to connect your picoPSU to a Vellerman or a Peaktech 6080 linear PSU for lab.use. It's cheap, in Europe it costs nearly 60 € , it get a limit of 3A of current delivered butin your setting could works easy, I think. You'll must only build a simple cable and start to know if the linear PSU is a valid solution or not, in your own system. Please, use picoPSU only for mobo. The P4 for CPU and all services (HDD, USB, CD-ROM) must be feeded by another PSU. I must stress the concept "less is better" for a PC audio, so linear PSU is only a step in the stairs to heaven , but your system is in the right way for excellence ;). Next big step for you, IMHO; is the cMP2 but if you don't try it it's impossible to me speak about it, you must listen to with your ears. Any words about cMP2 sound quality could be taken like an overstatement.
I get strong doubt about your PCI-E/PCI adapter, it seems to me a complicate item, I've nearly sure that SQ worses with it . Better a PCI-E sound card.

i2k92

12th August 2011 10:19 PM

I read somewhere that SMPS also dumps it's noise into the mains power line. Replace it with linear PS will help to clean up the power line..

audiodany

12th August 2011 10:47 PM

Absolutely agree. But also items like HDD, CD rom and fans put a lot of dirty in the power line and, worst, inside mobo elecrtic line increasing the jitter. From here start the cics' phylosophy about reduce every tension, every current, every device not useful for music reply (i.e. video board, fans, internal HDD) until the last stable low setting.
In this case a linear PSU is indubitably useful and get a great impact on sound quality